Topological transport theory - Y. Sun
The interplay between electromagnetic response theory and the symmetry plays a crucial role to understand the electrical and optical transport in condensed matter. In linear response region, the enhanced Berry curvature combined with its intrinsic topological charge and magnetism, the topological systems are often characterized by novel transport properties, such as anomalous Hall effect, topological Hall effect, spin Hall effect, anomalous Nernst effect, magneto-optical effect, as well as different types of magnetoresistances, etc. In the systems where the linear responses are forbidden by specific symmetries, the transport properties can be dominated by higher order responses, including seconder order anomalous Hall effect, giant bulk photovoltaic effect, and quantized circular photogalvanic effect etc.
Our interest is to understand and predict material properties from the viewpoint of electromagnetic response theory, symmetry and topology. In combination with model Hamiltonians and density functional theory, we aim to build the bridge between the fundamental theories of physics and experiments via the realization of interesting physical properties in real materials.
We also have extensive experimental collaborations with Professor Claudia Felser’s group. The joint interests are mainly focused to discover and utilize exotic properties in topological and magnetic materials, including transport, spintronics, catalyst, topological surface states, as well as material database development, etc.